FWIW,
I wouldn’t buy any generator except a Honda. Super quiet and super reliable.
Having said that, generator on a boat is going to present some adding concerns, gasoline generators produce CO. You can put it on the swim step I suppose to avoid the CO but they also have hot exhaust. If you have lead acid batteries and are charging them they will produce hydrogen gas in the compartments where they are situated.
IMHO if you want to have long lasting power out of your batteries, I’d have a on board smart battery charger like the NOCO or MinnKota precision series that stays plugged in when the boat is not in use. The other option is to go with LiFePO4 house batteries such as the Battle Born 100ah or the Relion 100ah / aka tracker battery at Cabela’s or Bass Pro shops. I know they are expensive, but even over the short term they cost less per kWh than lead acid batteries do, and over the long run they are significantly less per kWh than lead acid batteries.
I’ve recently wrapped up a pretty intensive LiFePO4 battery research project and at the end of the day the Battler Born 100ah internally heated batteries are the only ones that suit my needs. LiFePO4 batteries don’t like being charged below 32* and the battle born batteries have an internal heating model which will work well for me during the shoulder seasons when it gets pretty cold at night. Pretty sure the bms in the battle born will not allow any of their batteries to charge if they are too cold. The ReLion 100ah LT batteries also have internal heaters but they cannot be tied in series, only parallel and that does not meet my needs, and their BMS will allow the batteries to charge when they are too cold. All that being said, if you are not using and or charging the batteries when it is that cold out then it probably won’t matter to you.
Having said that, if you were to replace, I‘m assuming single group 27 90ah (roughly 40ah useable) group 27 house battery, with one or two group 31 100 ah (roughly 80-90ah useable per battery) LiFePO4 batteries you would probably have more than enough power for any outing, without the noise, complexity, or fumes of a generator. Two group 31 100ah LiFePO4 batteries weigh about the same as one group 27 90ah lead acid battery and would have roughly 400% more KWh’s than the single group 27 lead acid battery, and they don’t have the acid or hydrogen vapors that lead acid batteries do. Even just replacing your single group 27 lead acid battery with one group 31 LiFePO4 would increase your KWh‘s by over 200%.
I know that is not exactly what you asked for but hope that helps!
